Lighting system for automobiles



April 29, 1941. R. c. BRATT 2,239,838

LIGHTING SYSTEM FOR AUTOMOBILES Filed Feb. 7, 1940 INVENTQR Robert C Bruit ATTORNEYS Patented Apr. 29, 1941 UNITED STATES PATENT OFFICE 3 Claims.

This invention relates to electric lighting circuits for automobiles, and more particularly to an automatic safety device for automobiles.

It is an object of this invention to provide a system whereby both head lamps of an automobile will function even though one filament is burned out.

Another object of this invention is to provide a lighting system which, when either filament in one or both of the double filament head lamp bulbs burn out or otherwise fails, will automatically substitute the remaining filament in said bulb and also, at the same time, signal the operator that a filament has failed to light.

Many circuits have heretofore been proposed for automatically lighting either one or both of the dim lights of automobile head lamps when a bright light filament burns out, and for either lighting one or both of the bright lights when a dim light filament burns out, or for signaling the operator of the light failure. However, these systems have either been so complicated as to become impractical or expensive, or they have been undesirable in that two filaments are substituted when only one filament fails.

It is, therefore, another object'of this invention to provide a simplified lighting system which operates to turn on but one filament at the proper location when a filament failure occurs, and which signals the operator of such failure.

A further object of this invention is to provide a compact unit which can be readily installed in an automobile which has but one relay for each filament under consideration, and which signals the operator of any failure of said filaments.

Other objects will be apparent from the following detailed description of the appended drawing, where- Figure 1 is a diagram of an automobile lighting circuit embodying the present invention; and

Fig. 2 is a circuit diagram showing the manner of connecting an additional relay for indicating a failure of any other light, such as a tail light or parking light.

Referring more particularly to Fig. 1, H1 and H2 designate head lamps of an automobile having bright filaments B1 and B2, and dim filaments D1 and D2, respectively, and R1, R2, R3 and R4 each designate relays. Filaments D1 and D2 are located above the respective filaments B1 and B2 in order to direct the light downward. S indicates a signal light with a single filament. One terminal of a battery 2 is shown connected to a ground G, and the other terminal is connected through a light switch 3 and main light fuse 4 to a pole 5 of a suitable dimmer switch, which may be a foot switch F having an arm 6, which is shown in a position so that connection is made between the contact 5 and contacts 1 and 8 for operation of the dimmer filaments D1 and D2. The contact point I is connected by means of the wires 9 and H) to a terminal II of solenoid l2 in the relay R1. The other terminal I4 of the coil I2 is connected by means of a wire l5 through fuse 16 to a terminal I! of the filament D1. Terminal 8 of the switch F, which when the switch is in the full line position shown is also connected to the contact 5, is connected through a wire l8 and branch wire l9 to a terminal 20 of the relay coil or solenoid coil 2!. The other terminal 23 of the coil 2| is connected through a wire 24 and a fuse 25 to the terminal 26 of the filament D When the, switch F is moved. to the dotted position so that connection is made between the switch arm 6 and the terminals 21 and 28, these terminals then make electrical connection with terminal 5.

One of the contacts 28 is connected by means of the wire 30 and branch wire 3| to a terminal of the coil 32 of the relay R2. The other terminal of the solenoid coil 32 is connected through the wire 33 and fuse 34 to the terminal 35 of the filament B1. Common terminals 36 and 31 of the two filaments in each light are connected to the ground G. The other contact 21 of the switch F is connected through the wire 38 and the branch wire 39 to the terminal 40 of the relay coil or solenoid coil 4| in the relay R4. Terminal 42 is connected through the wire 43 and fuse 44 to the terminal 45 of the filament B2.

Terminal 1 of the switch F is also connected through the wire 9 and the branch wire 89 to the terminal 8T connected to the contact point 86 of the relay R2. The armature 85 of the relay R2 carrying contact 46 is adapted to break the connection between the terminal 81 and the wire 41 when the coil 32 is energized. Similarly, the armature 48 of the relay R1 is adapted to make and break the circuit between the wire 41 and the wire 30, (the wire 30 being connected to the contact 4 9 by the branch wire 29), as the coil l2 oi the relay R1 is de-energized and energized, respectively. The contact 50 which is carried by and insulated from the armature 48 is connected to the terminal 5|, which in turn is connected. both to the wire 41 and the terminal 5 of the switch F by means of the wire 52. When the coil 12 is energized, the contact 53 makes connection with contact 53 connected to the terminal 54, which is in turn connected by means of the wire 55 to the contact 51 of relay R3, and when the relay coil i2 is de-cnergiaed, the contact 50 makes connection with the contact 58 which is connected through terminal 59 and the wire Bil and terminal El to the contact 92 of relay R3. The movable contact 93, carried by and insulated from the armature 54 which is connected through the terminal 55 to the wire 41, makes connection through the loop H29 and the terminal 56 and wire 51 with the filament 68 of the signal lamp S, which is connected in series with the wire 61 and the ground G. The wire 41 is also connected through the wire and terminal 19 to the movable contact 46, which makes connection through the contact l l, terminal l2 and wire 13 with the contact '54 of the relay R4 as the coil 32 is tie-energized, and makes connection with the contact 15, which is connected to the contact '15 of the relay R4 as the coil 32 is energized. The movable contact Tl, carried. by and insulated from the armature i8, is connected to the wire 51 through the wire 9. The wire I8 is connected by the wire 81! to the contact 9|, which makes connection through the armature 19 with the wire 41 when the coil M of the relay R4 is de-energized.

In the operation of the apparatus, as shown in Fig. 4, with the switch F arranged to connect contacts 1 and 8 with terminal 5, part of the current from the battery flows through each of the coils I2 and 2| of the relays R1 and R3 to each of the filaments D1 and D2, causing them to glow. The current through the coils l2 and 2| causes the armatures 49 and 64 to be moved against the force of the tension springs 99 and 9| so that connections between contact 49 and armature 48, and between contact 84 and armature 94 are broken. At the same time, connection is made between terminals and 53, and between 66 and 62.

If, for example, filament D1 should fail or a short should occur, blowing line fuse l6, coil l2 of relay R1 would be tie-energised, allowing the armature 48 to be withdrawn by spring 99 so that connection is made between the contact 49 and the wire 41. This permits current to pass from the wire 41 through the armature 48, the contact 49, the wires 29 and 3|, the coil 32 of the relay R2, the wire 33 and the fuse 34, to the filament Bl, causing it to light so that a light is maintained in each of the lights H1 and H2. Current then passing through the coil 32 moves the armature 85 against the force of the tension spring 92 so that connection between terminal 86 and the armature 85 is broken and connection is made between terminal and contact I5. This last connection permits current to flow from the battery through wire 52, terminals 5|, 58 and 59, through wire 59, terminals El, 92 and 69, and thence through wire 51 to filament 68 of the signal light S, causing it to light, and signaling the operator that the current through filament D1 has failed.

If the filament D2 should fail instead of the filament D1, the coil 2| of the relay R3 would be deenergized, allowing the armature 54 to be moved by the tension of the spring 9| into contact with contact 84 so that current would flow from. the wire 41 through the armature 54, the terminal 84 and the wire 39, through the coil 4| of relay R4, and through the wire 43 and the fuse 44 to the filament B2. At the same time, armature i8 is drawn to its upper position (looking at Fig. 1) and the movable contact 11 is connected to the terminal 14, allowing current to pass from the wire 41, along the wire 69, through points I0, 45, H and 12, along the wire 13, through points 14 and I1, and through the wires 19 and 61 to light the filament 98 of the signal lamp S, which would inform the operator of the car that one of the filaments, such as D2, has failed to light.

When the switch F is moved so that connection is made between terminal 5 and contacts 21 and 23, coils I2 and 2| of relays R1 and R3 are deenergized, allowing the armatures 4B and 64 to be moved by action of the springs 99 and 9| so that connection is made between terminal 65 and the contact 84, and between armature 48 and terminal 49. At the same time, current passes between the terminal 5 and terminals 21 and 28, along the wires 30, 3| and 39, 39, through the coils 32 and 4|, through the wires 33 and 43 and the fuses 34 and 44 to light the filaments B1 and B2. Current through the coils 32 and 4| moves the armatures and 18 against the tension of springs 92 and 94 so that electrical connection between armature I8 and contact BI, and between armature 85 and contact 86 is broken, and connection is made between terminal 19 and contact 15, and between the wire 19 and con tact '14.

If current should stop flowing through the filament E1, the coil 32 would be de-energized and permit the spring 92 to withdraw the armature so that connection would be made between the wire 4'! and the terminal 85 through the arn'iature. This would allow current to be withdrawn from the wire 41 through the armature 85 and pass through the wire 89, which is in electrical connection with the filament Di, thus causing the filament D1 to light. At the same time, connection is made between the contacts 46 and II, which permits current to pass along the wire 59 to the wire 13 and through points 14, I1 and i3, and the wire l9, and along wire 61 to light the filament 98 of the signal light S, thus indicating a burned out filament.

If the filament B2 should fail, or if the circuit through that filament should be broken, coil 4| of the relay R4 would be de-energized and the armature 18 would be moved by the spring 94 into connection with contact 8|. Current would then be passed from wire 41 through the armature and contact 8|, along wires 89 and I9, through the coil 2| to light filament D2. At the same time, current would pass from the wire 69, between terminal 19 and contact 15, then through the connection between contacts 16 and 11, along wires '59 and 51 to light the filament 68 of the signal light S to signal the operator that a filament has failed to light.

If it should also be desired. to indicate the failure or other lights, as for example a tail light or parking light T having a filament P1 as illustrated in Fig. 2, a relay, as above described, should be connected into the light circuit with the coil Hlil in series with the filament. Then terminal llli may be connected to the terminal |t3 of the light switch L, which has terminal I94 suitably connected to the battery 2, and terminal |05 may be connected to the ungrounded terminal of filament Pl. Terminal I52 is connected to the ungrounded terminal of the filament 98 of the signal light S at a suitable point A, which may be located on the wire 61, as shown in Fig. l. A relay may similarly be connected into the circuit of each light where indication of failure is desirable. Should the current through the filament P1 be interrupted between the terminal HH and the ground, current will fiow between terminals I! and IE2, and thence to A on wire 61 and along the wire 61 to light the signal lamp.

One of the advantages of this invention is realized from the fact that I use but one relay or solenoid coil per head light filament and yet obtain both a substitution of the appropriate dim light for a bright filament should the latter fail to light, and a substitution of the appropriate bright light filament when a dim light fails. In addition, a single signal light is lighted when any of the filaments fail to light.

Furthermore, it is to be understood that the particular form of apparatus, shown and described, is presented for purposes of explanation and illustration, and that various modifications of said apparatus can be made without departing from my invention as defined in the appended claims.

What I claim is:

1. An electrical lighting system for automobiles comprising two head lamps with at least a dim filament and a bright filament each, a light switch, a source of electrical energy, only two separate relays for each of said head lamps, each relay having a single solenoid operating coil, which is connected in series with only one of said filaments, and normally closed main contacts, and a manually operable selector switch for selectively connecting said bright filament or a the dim filaments and the respective ope-rating coils in series therewith to said source of energy, one terminal of the operating coil of each relay being permanently connected to a terminal of said selector switch, the other terminal being permanently connected to a single filament, one of said main contacts of each relay being movable and being connected through said light switch to said source of energy regardless of the position of said selector switch, the other of said main contacts of each relay being stationary and being electrically connected to the operating coil of the other relay for the same lamp, said main contacts of each relay being opened by the operating coil only when lighting current passes therethrough, any relay having a coil in series with a manually connected filament being automatically operable by a failure of current fiow through said manually connected filament to divert the current to a manually unconnected filament of said lamp without affecting the connection of the other head lamp.

2. An electrical lighting system for automobiles comprising two head lamps with at least a dim filament and a bright filament each, a light switch, a source of electrical energy, an auxiliary light, a signal light, two separate relays for each of said head lamps, each relay for said head lamps having only one solenoid operating coil, which is connected in series with only one of said filaments, normally closed main contacts and auxiliary contacts, a single relay having a coil in series with said auxiliary light and having normally closed aurdliary contacts, and a manually operable selector switch for selectively conneeting said bright filament or said dim filament and the respective operating coils in series therewith to said source of energy, one terminal of each of said operating coils being permanently connected to a terminal of said selector switch and one terminal being permanently connected to only one of said filaments, one of said main contacts of each head lamp relay being movable and being connected through said light switch to said source of energy regardless of the position of said selector switch, the other of said main contacts in each relay being permanently electrically connected to the operating coil of the other relay for the same head lamp, any head lamp relay having a coil in series with any manually connected filament being automatically operable by a failure of current fiow through said manually connected filament to close said main contacts and to divert the current to a manually unconnected filament of the same lamp without affecting the connection to the filament of the other head lamp, said auxiliary contacts being connected in a signalling circuit having only one signal light and being operated by a failure of current to flow through a manually connected fila ment so as to connect said signal light to said source of energy.

3. An electrical lighting system for automobiles comprising two head lamps with at least a dim filament and a bright filament each, a light switch, a source of electrical energy, a signal light, only two separate relays for each of said head lamps, each relay having only one solenoid operating coil, which is connected in series with only one of said filaments, normally closed main contacts and auxiliary contacts, and a manually operable selector switch for selectively connecting said bright filament or said dim filament and the respective operating coils in series therewith to said source of energy, one terminal of each operating coil being permanently connected to a terminal of said selector switch and one terminal being connected to only one of said filaments, one of said main contacts of each relay being connected through said light switch to said source of energy regardless of the position of said selector switch, the other of said main contacts in each relay being electrically connected to the operating coil of the other relay for the same lamp, any relay having a coil in series with a manually connected head lamp filament being automatically operable by failure of current flow through said manually connected filament to divert the current to a manually unconnected filament of the same lamp without affecting the connection of said other head lamp, said auxiliary contacts of each relay being connected in a signal circuit having only one signal light, the auxiliary contacts of the relays of a lamp having a failure of energy fiow through any manually connected filament being adapted to be operated by such failure to connect said signal light to said source of energy.

ROBERT C. BRAT'I. 

